Multiple electrical outlet strips are very useful devices for facilitating the operation of multiple electrically powered components at a single location. Conventional multiple electrical outlet strips, such as shown in U.S. Pats. Nos. 2,743,423 and 4,113,334, usually comprise a metal casing having a plurality of outlet receptacles received by openings in one face of the casing, and connected together internally by a number of wires. Normally the outlet receptacles are integral components with their own terminals for receipt of male electrical plug prongs, with the outlet receptacles electrically interconnected by conventional wiring. Proposals have been made (see copending application Ser. No. 190,050 filed Sept. 23, 1980) for allowing the common wiring to provide the electrical contacts for the outlet receptacles, with the receptacles mounted within the casing in basically the same manner. Conventional housings for multiple electrical outlet strips are usually provided by pre-sized cans, or metal extrusions.
While conventional multiple electrical outlet strips perform their intended functions well, the costs of construction thereof are higher than desirable. The utilization of outlet receptacles requires that the receptacles be wired to each other and to the power source, and high labor costs are often associated therewith for the wiring of the receptacles together and the insertion of the receptacles into the casing. Additionally, the provision of the multiple receptacles provides relatively high component costs, and minimizes the flexibility of forming multiple electrical outlet strips of varying numbers of plug positions.
According to the present invention a multiple electrical outlet strip, and method of production thereof, are provided that result in the extremely inexpensive construction thereof. An outlet strip according to the invention is produced with a minimum of tooling costs as well as a minimum of labor costs, yet the outlet strip according to the invention has even better mechanical and electrical properties than conventional multiple electrical outlet strips. Once the length of the strip has been established, the cost will be the same irrespective of how many outlets it has since individual outlet receptacles are not utilized.
According to the present invention a multiple electrical outlet strip is produced by extruding an elongated housing from electrically insulating material (preferably plastic). The housing extrusion has at least a top surface and side walls, and includes elongated electrically conductive material-receiving interior channels. The elongated housing extrusion is severed to provide a housing of a predetermined length having opposite open ends, and a plurality of spaced through-extending openings are formed in the housing top surface adjacent the electrically conductive material-receiving interior channels. The openings comprise at least two spaced sets of spaced openings for receipt of male electrical plug prongs. Electrically conductive material, such as brass strips with locking portions, is inserted into operative association with each of the electrically conductive material-receiving interior channels, the locking portions maintaining the strips in place within the housing. The brass strips are electrically interconnected to an electricity conducting element, such as a conventional electrical cord, which extends exteriorly of the housing. Wire sections from the stripped end of an electrical cord may be brought into contact with the brass strips to effect this interconnection. End covers are then connected to the open ends of the housing, providing a complete multiple electrical outlet strip.
Preferably the extruding of the housing is accomplished by extruding a channel-shaped housing having an open bottom, and a bottom member adapted to cooperate with the open bottom of the housing is also extruded. Preferably interlocking portions on the housing and bottom are extruded and the bottom, once cut to the appropriate length, is slid into operative association with the housing, and can be held in place by the end covers. A plurality of self-tapping screw-receiving channels are preferably extruded in the interior of the housing and the end covers are connected to the open ends of the housing by passing self-tapping screws through each of the end caps into operative association with the screw-receiving channels which have been extruded.
In order to provide guidance of male plugs into the openings formed in the housing top surface therefor, upwardly-opening guide channels are extruded in the exterior of the top surface of the housing, and the openings are formed within the guide channels. Cover-receiving surface manifestations also are desirably extruded in the housing, and a cover of electrical insulating material having surface manifestations cooperating with the housing surface manifestations is preferably extruded and moved into operative association with the housing to cover any desired number of male electrical plug prong-receiving openings in the top of the housing.
The same extrusion profile is used for both the back cover and the top ind. outlet slideing covers.
It is the primary object of the present invention to provide an inexpensively constructed improved multiple electrical outlet strip. This and other objects of the invention will become clear from the detailed description of the drawings, and from the appended claims.